A legendary trio is a term used to describe a group of three closely-related legendary Pokémon. Legendary trios can be subdivided into two tiers, normal trios and mascot trios. Normal trios, which are always the first legendaries that appear in any Pokédex order, are allowed into the many Battle Towers and other battle facilities. They are also the only Pokémon whose base stats total to 580. The mascot trios, whose name comes from the fact that all of them are version mascots, are not allowed in the Battle Tower, and are found close to the end of the Pokédex in the generation of their release.
Many trios, in addition to sharing at least one type, will far more commonly share their ability and base stat totals (though Rayquaza does not with the other members of its trio). Several of the trios have a master who created them or somehow is able to exert control over them.
